problems in setting example project in java

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my problem comes from this tutorial http://docs.opencv.org/trunk/doc/tutorials/introduction/desktop_java/java_dev_intro.html section "SBT project for Java and Scala".

When I run sbt, it throws an exception "no opencv_java246 in java.library.path".

so i type sbt -Djava.library.path=%my_native_library_path% run to set the java library path, it will not throw exception and have desired result.

But I don't want to specify the native java library path every time when I run sbt. Is there a way to assign it at the beginning and use it as a default? Thanks!